Polymerization of epoxides



United States Patent Ofiice 3,274,129 Patented Sept. 20, 1966 3,274,129 POLYMERIZATION F EPOXIDES Frederick E. Bailey, Jr., Charleston, W. Va., assignor to Union Carbide Corporation, a corporation of New York No Drawing. Filed June 29, 1959, Ser. No. 823,364 Claims. (Cl. 260-2) This invention relates to a process for polymerizing epoxide compounds.

In a broad aspect the instant invention is directed to the process for polymerizing vicinal-epoxy hydrocarbon free of unsaturation other than aromatic unsaturation in contact with a cataiytically significant quantity of certain divalent metal-containing compounds described hereinafter to produce useful polymers.

It is deemed appropriate at this time to define the term reduced viscosity since this term will be frequently employed in the specification. By the term reduced viscosity, as used herein including the appended claims, is meant a value obtained by dividing the specific viscosity by the concentration of the polymer in the solution, the concentration being measured in grams of polymer per 100 milliliters of solvent at a given temperature. The reduced viscosity value is regarded as a measure of molecular weight. The specific viscosity is obtained by dividing the difference between the viscosity of the solution and the viscosity of the solvent by the viscosity of the solvent. Unless otherwise indicated, the reduced viscosity value is determined at a concentration of 0.2 gram of polymer per 100 milliliters of solvent, i.e., acetonitrile at 30 C.

Accordingly, one or more of the following objects will be achieved by the practice of this invention.

It is an object of this invention to provide a novel process for polymerizing vicinal-epoxy hydrocarbon free of unsaturation other than aromatic unsaturation in contact with a catalytically significant quantity of certain divalent metal-containing compounds to produce useful polymers. It is also an object of this invention to provide a novel process for polymerizing an admixture containing two or more different vicinal-epoxy hydrocarbons which are free of unsaturation other than aromatic unsaturation in contact with a catalytically significant quantity of certain divalent metal-containing compounds as catalysts therefor. Another object of this invention is to prepare solid polymers in accordance with the teachings herein set forth. A further object of this invention is directed to the preparation of resinous poly(ethylene oxide). Other objects will become apparent to those skilled in the art in the light of the instant specification.

The vicinal-epoxy hydrocarbons free of unsaturation other than benzenoid unsaturation, i.e., vicinal-epoxy hydrocarbons which have a single vicinal epoxy group and which are free from unsaturation other than benzenoid unsaturation, which can be employed in the polymerization process of the invention can be characterized by the following formula:

wherein each R individually, can be hydrogen or a hydro carbon radical free from ethylenic and acetylenic unsaturation such as, for example, alkyl, aryl, cycloalkyl, aralkyl, 6

from a saturated cycloaliphatic hydrocarbon nucleus containing from 4 to 10 carbon atoms, preferably from 4 to 8 carbon atoms, such as, for example, a nucleus derived from cycloaikane, alkyl-substituted cycloalkane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, Z-methylcyclopentane, 3-amylcyciohexane, and the like. Illustrative R radicals include, among others, methyl, ethyl, propyl, butyl, isobutyl, hexyl, isohexyl, 3-propylheptyl, dodecyl, octadecyl, phenyl, benzyl tolyl, ethylphenyl, butylphenyl, phenethyl, phenyipropyl, cyclopentyl, cyclohexyl, Z-methylcyclohexyl, cyclohe-ptyl, and the like.

Illustrative vicinal-epoxy hydrocarbons which can be employed in the polymerization process of this invention include, for example, ethylene oxide, propylene oxide, 1,2- epoxybutane, 2,3-epoxybutane, the epoxypentanes, the epoxyhexanes, the epoxyheptanes, 2,3-epoxyheptane, 5- butyl-3,4-epoxybutane, 1,2-epoxydodecane, 1,2-epoxyoctadecane, styrene oxide, ortho-, meta-, and para-ethylstyrene oxide, the oxa-bicycloalkanes, e.g., 7-oxabicyclo- [4.1.0]heptane, 6 oxabicyclo[3.1.0]hexane, 4 propyl-7- oxabicyclo[4.1.0]heptane, and the like. The lower olefin oxides, that is, ethylene oxide, propylene oxide, and the epoxybutanes are especially suited to prepare high molecular weight products. A single vicinal-epoxy hydrocarbon or an admixture of at least two different vicinalepoxy hydrocanbons can be employed as the monomeric feed. In polymerizing an admixture comprising two different vicinal-epoxy hydrocarbons, it is preferred that one of them be a lower olefin oxide.

The catalysts which can be employed in the polymerization reaction are the phosphates, aluminates, borates, and molybdates of divalent metals which have an atomic number greater than 11 and less than 57 of Group II of the Periodic Table. These divalent metals include magnesium, calcium, zinc, strontium, cadmium and barium. Illustrative catalysts include, among others, calcium aluminate, calcium molybdate, barium borate, zinc phosphate, zinc aluminate, calcium pyrophosphate, magnesium aluminate, strontium molybdate, cadmium phosphate, barium aluminate, and the like. The calcium-containing catalysts are especially preferred.

The catalysts are employed in catalytically significant quantities, and, in general, a catalyst concentration in the range of from about 0.1, and lower, to about 10.0 weight percent, and higher, based on the total weight of monomeric material, is suitable. A catalyst concentration of from about 0.3 to about 5.0 weight percent is preferred. For optimum results, the particular catalyst employed, its surface area, the nature of the monomeric reagent(s), the operative temperature at which the polymerization reaction is conducted, and other factors will largely determine the desired catalyst concentration.

The polymerization reaction can be effected over a wide temperature range. In general, a reaction temperature in the range of from about 50 C., and lower, to about 150 C. is suitable. A reaction temperature in the range of from about to about C. is preferred. As a practical matter, the choice of the particular temperature at which to effect the polymerization reaction depends, to an extent, on the nature of the vicinal-epoxy hydrocarbon reagent(s) and particular catalyst employed, the concentration of the catalyst, and the like.

In general, the reaction time will vary depending on the operative temperature, the nature of the vicinal-epoxy hydrocarbon reagent(s) employed, the particular catalyst and the concentration employed, the choice and amount of an inert, normaliy-liquid organic vehicle, and other factors. The reaction time can be as short as a few hours in duration or it can be as long as several days.

When polymerizing an admixture containing two different vicinal-epoxy hydrocarbons, the proportions of said vicinai-epoxy hydrocarbons can vary over the entire range. Preferably the concentration of either monomeric vicinal-epoxy hydrocarbon is in the range of from about 5 to about 95 weight percent, based on the total weight of said vicinal-epoxy hydrocarbons.

The polymerization reaction preferably takes place in the liquid phase. Preferably, the polymerization reaction is conducted under an inert atmosphere, e.g., nitrogen. It is also desirable to effect the polymerization process under substantially anhydrous conditions.

The polymerization reaction can be carried out in the presence of an inert normally-liquid organic vehicle such as, for example, aromatic solvent, e.g., benzene, toluene,

xylene, ethylbenzene, chlorobenzene, and the like; various oxygenated organic compounds such as anisole, the

dimethyl and diethyl ethers of ethylene glycol, of propylene glycol, of diethylene glycol and the like; normally liquid saturated hydrocarbons including the open chain, cyclic, and alkyl substituted cyclic saturated hydrocarbons such as pentane, hexane, heptane, various normally-liquid petroleum hydrocarbon fractions, cyclohexane, the alkylcyclohexanes, decahydronaphthalene, and the like.

An induction period may be observed in that the polymerization is not initiated immediately. The induction period can be as short as minutes in length with the more active catalysts or it can be several hours in duration. This induction period depends, for example, on the individual catalyst employed, its preparation, its surface area,

the nature of the monomeric feed, the reaction temperature, the purity of the monomeric feed, and other factors. Unreacted monomeric reagent can be recovered from 'the reaction product by conventional techniques such as mer, thus resulting in precipitating the polymer product.

The precipitated polymer is readily recovered by filtration, decantation, etc., followed by drying same under reduced pressure at slightly elevated temperatures.

The products of the polymerization process are valuable and useful polyethers. The viscous liquid to waxlike polymers can be employed as solvents, raw materials and plasticizing agents for resins, and the like. The solid polymers are useful for the production of various shaped articles, e.g., buttons, brush handles, etc. The polymers are also useful as lubricants, vehicles, and intermediates in industries such as the food, pharmaceutical, textile, and petroleum industries. Resinous ethylene oxide polymers are useful as sizing agents, coagulants, and watersoluble lubricants. The water-soluble and water-insoluble solid polymers are also useful in the preparation of films by conventional techniques such as by milling on a two-roll mill, calendering, solvent casting, and the like.

In illustrative Examples 1-7 below, the procedure employed, unless noted otherwise, to prepare the polymer was as follows. A 9-inch Pyrex tube 22 mm. in diameter was sealed at one end; the other end of the tube was fitted with a 3-inch piece of 8 mm. Pyrex tubing. The tube was cleaned, dried and flushed with dry nitrogen; 21 weighed quantity of catalyst was then introduced into the tube. The monomeric mixture was charged to the tube in a dry box containing a nitrogen atmosphere. The tube was then closed with a rubber cap, followed by cooling in Dry Ice-acetone bath; the tube was sealed under the vacuum thus obtained. The sealed tube was subsequently inserted into an aluminum block or placed in a constant- Ytemperature bath, said aluminum block (or tube) being agitated by rocking at the desired operating temperature for a given period of time. After this, the tube was broken open and the reaction product was freed of unreacted monomer, if any, by drying same under reduced pressure at slightly elevated temperature.

Example 1 To a Pyrex glass tube, there were charged 30 grams of ethylene OXide and 0.9 gram of calcium aluminate. The tube was sealed and then inserted into an aluminum block which was gently agitated for a period of 89 hours at 90 C. At the end of this period of time the tube was broken open and the reaction product was freed of unreacted monomer by drying same under reduced pressure at slightly elevated temperature. There was obtained 1 gram of a solid water-soluble polymer which had a reduced viscosity value of 0.63 in acetonitrile.

Example 2 To a Pyrex glass tube, there were charged 30 grams of ethylene oxide and 0.9 gram of calcium phosphate. The tube was sealed and then inserted into an aluminum block which was gently agitated for a period of 70 hours at 90 C. At the end of this period of time the tube was broken open and the reaction product was freed of unreacted monomer by drying same under reduced pressure at slightly elevated temperature. There were obtained 13 grams of a hard, tough, water-soluble polymer which had a reduced viscosity value of 5.6 in acetonitrile.

In an analogous manner, propylene oxide can be homopolymerized in the presence of 0.5 weight percent magnesium aluminate, under the operative conditions noted above, to give a solid, water-insoluble polymer.

Example 3 To a Pyrex glass tube, there were charged 30 grams of ethylene oxide and 0.9 gram of calcium phosphate. The tube was sealed and then inserted into an aluminum block which was gently agitated for a period of 70 hours at 90 C. At the end of this period of time the tube was broken open and the reaction product was freed of unreacted monomer by drying same under reduced pres sure at slightly elevated temperature. There were obtained 30 grams of a hard, tough, water-soluble polymer which had a reduced viscosity value of 4.6 in acetonitrile.

In an analogous manner, 1,2-butylene oxide can be homopolymerized in the presence of 1.0 weight percent zinc phosphate, under the operative conditions noted above, to give a paste-like, water-insoluble polymer.

Example 4 To a Pyrex glass tube, there were charged 30 grams of ethylene oxide and 0.9 gram of calcium aluminate. The tube was sealed and then inserted into an aluminum block which was gently agitated for a period of 65 hours at 90 C. At the end of this period of time the tube was broken open and the reaction product was freed of unreacted monomer by drying same under reduced pressure at slightly elevated temperature. There were obtained 3 grams of a hard, firm, water-soluble polymer which had a reduced viscosity value of 0.82 in acetonitrile.

Example 5 To a Pyrex glass tube, there were charged 30 grams of ethylene oxide and 0.9 gram of calcium molybdate. The tube was sealed and then inserted into an aluminum block which Was gently agitated for a period of 65 hours at 90 C. At the end of this period of time the tube was broken open and the reaction product was freed of unreacted monomer by drying same under reduced pressure at slightly elevated temperature. There was obtained 1 gram of a solid, water-soluble polymer which had a reduced viscosity value of 0.57 in acetonitrile.

Example 6 To a Pyrex glass tube, there were charged 30 grams of ethylene oxide and 0.9 gram of calcium pyrophosphate.

The tube was sealed and then inserted into an aluminum block which was gently agitated for a period of 21.5 hours at 90 C. At the end of this period of time the tube was broken open. There were obtained 30 grams of a hard, tough, water-soluble polymer which had a reduced viscosity value of 12.3 in acetonitrile.

In an analogous manner, an admixture containing 80 parts by weight of ethylene oxide and 20 parts by weight of propylene oxide can be copolymerized in the presence of 2 parts by Weight of Zinc pyrophosphate, under the operative conditions noted above, to give a solid, watersoluble copolymer.

Example 7 To a Pyrex glass tube, there were charged 30 grams of ethylene oxide and 0.9 gram of calcium pyrophosphate. The tube was sealed and then inserted into an aluminum block which was gently agitated for a period of 21.5 hours at 90 C. At the end of this period of time the tube was broken open. There were obtained 30 grams of a hard, tough, water-soluble polymer which had a reduced viscosity value of 5.1 in acetonitrile.

In an analogous manner, an admixture containing 85 parts by weight of ethylene oxide and 15 parts by weight of cyclohexene oxide can be copolymerized in the presence of 3 parts by Weight of calcium pyrophosphate, under the operative conditions noted above, to give a solid, watersoluble copolymer.

Example 8 To a Pyrex glass tube there were charged 30 grams of ethylene oxide and 0.9 gram of barium borate. The tube was sealed and then placed in a constant temperature bath, maintained under mild agitation, for a period of 64 hours at 90 C. At the end of this period of time the tube was broken open and the reaction product was freed of unreacted monomer by drying same under reduced pressure at slightly elevated temperature. There were obtained 15 grams of a hard, tough, water-soluble polymer which had a reduced viscosity value of 2.3 in acetonitrile.

Although the invention has been illustrated by the preceding examples, the invention is not to be construed as limited to the materials employed in the above-said exemplary examples, but rather, the invention encompasses the generic areas as hereinbefore disclosed. Various modifications and embodiments of this invention can be made without departing from the spirit and scope thereof.

What is claimed is:

1. A polymerization process which comprises contacting a lower olefin oxide with from about 0.1 to about 10.0 weight percent, based on the said lower olefin oxide, of a catalyst selected from the group consisting of phosphates, aluminates, borates and molybdates of divalent metals having an atomic number greater than 11 and less than 57 of Group II of the Periodic Table; at a temperature in the range of from about 50 to about 150 C. for a period of time suflicient to produce a solid polymer of said lower olefin oxides having a reduced viscosity value of from 0.57 to 12.3 determined at a concentration of 0.2 gram of polymer per milliliters of acetonitrile at 30 C.

2. The process of claim 1 wherein said catalyst is calcium aluminate.

3. The process of claim 1 wherein said catalyst is calcium molybdate.

4. The process of claim 1 wherein said catalyst is calcium phosphate.

5. The process of claim 11 wherein said catalyst is calcium pyrophosphate.

6. The process of claim 1 wherein said catalyst is calcium borate.

7. A polymerization process which comprises contacting an admixture containing at least two lower olefin oxides with from about 0.1 to about 10.0 weight percent, based on the said lower olefin om'de, of a catalyst selected from the group consisting of phosphates, alum-inates, and *borates and molybdates of divalent metals having an atomic number greater than 11 and less than 57 of Group II of the Periodic Table; at a temperature in the range of from about 50 to about 150 C. for a period of time sufiicient to produce a solid copolymer of said lower olefin oxides.

8. The process of claim 7 wherein said olefin oxides are ethylene oxide and propylene oxide.

9. A process which comprises contacting ethylene oxide with a catalytcially significant quantity of a catalyst selected from the group consisting of phosphates, aluminates, borates, and molybdates of divalent metals which have an atomic number greater than 11 and less than 57 of Group II of the Periodic Table; at a temperature in the range of from about 70 to about C.; and for a period of time suificien-t to produce solid po1y(ethylene oxide).

10. The process of claim 9 wherein said catalyst is barium borate.

References Cited by the Examiner UNITED STATES PATENTS 1,921,378 8/1933 Webel 260-2 2,801,228 7/1957 Stanck et a1. 26047 2,886,472 5/ 1959 Condo et a1. 26047 2,911,377 11/.1959 Gurgiolo et al. 2602 2,917,470 12/ 1959 Bressler et al. 260-2 3,018,262 1/1962 Schroeder 2 60--2 OTHER REFERENCES Lee et al.: Epoxy Resins, McGraw-Hill Book Co., Inc., N.Y. (#1957), page 74 relied upon.

Hackhs Chemical Dictionary, third edition, pp. 158, 159, McGraw-Hill Book 00., Inc., N.Y., 1944.

LO'UISE P. QUAST, Primary Examiner.

WILLIAM H. SHORT, HAROLD BURSTEIN, MIL- TON STER-MAN, Examiners.

T. D. KERWIN, P. H. HELLER, Assistant Examiners. 

1. A POLYMERIZATION PROCESS WHICH COMPRISES CONTACTING A LOWER OLEFIN OXIDE WITH FROM ABOUT 0.1 TO ABOUT 10.0 WEIGHT PERCENT, BASED ON THE SAID LOWER OLEFIN OXIDE, OF A CATALYST SELECTED FROM THE GROUP CONSISTING OF PHOSPHATES, ALUMINATES, ORATES AND MOLYBDATES OF DIVALENT METALS HAVING AN ATOMIC NUMBER GREATER THAN 11 AND LESS THAN 57 OF GROUP II OF HE PERIODIC TABLE; AT A TEMPERATURE IN THE RANGE OF FROM ABOUT 50* TO ABOUT 150* C. FOR A PERIOD OF TIME SUFFICIENT TO PRODUCE A SOLID POLYMER OF SAID LOWER OLEFIN OXIDES HAVNG A REDUCED VISCOSITY VALUE OF FROM 0.57 TO 12.3 DETERMINED AT A CONCENTRATION OF 0.2 GRAM OF POLYMER PER 100 MILLITERS OF ACETONITRILE AT 300*C. 